Noxious or offensive odors in rooms that house conventional or industrial toilet systems or functional equivalents thereof is an age-old problem. Building codes frequently require rooms in which toilets are housed to have an exhaust system to remove moisture from the room, but these systems are terribly inadequate when it comes to removing odors. Typically, exhaust systems consist of a vent in the ceiling with a fan to generate air flow out of the room. These systems are neither efficient nor effective. Ceiling vents/fans are removing odors far from the source of the odors, rendering these systems both ineffective as odor removal systems, and inefficient, in regards to their energy consumption. Additionally, most of the air removed is not offensive, and frequently the air removed by the system is air heated (or often cooled) by the building's HVAC system, and therefore the removal thereof is a waste of energy. These fans also need to operate long after use to remove what odors they can. Typically, the fan is often left operating long after odors have drifted into other rooms in the building and is no longer removing odors, thereby wasting additional energy. In some industrial (public) bathrooms, fans are continuously running. Retrofitting an exhaust system onto or into a conventional toilet flushing system to solve these problems and more efficiently remove odors has been the common design solution/improvement to the ineffective and inefficient ceiling vent/fan system, however, these retrofitted systems have inherent drawbacks. They must be fitted to existing toilet systems, which can significantly vary in size and design, and typically require assorted gadgetry to accomplish the "retrofit." They are also ineffective, often inefficient, and cumbersome, unsightly, and costly.
The prior art is replete with retrofitted air exhaust systems which can be divided into two convenient categories of design solutions which are retrofitted to a conventional toilet (water flushing) system, and in the later category, which can also be retrofitted to an industrial toilet system. The systems falling under the first category utilize the conduits, ducts, and apertures in the toilet stool, which in the conventional design delivers the water from the water tank into the conduit, through the ducts and out the apertures within the toilet stool, and into the toilet bowl, as a path for odor/air removal from the toilet bowl; the direction of air flow is in the opposite direction of the water flow. These designs typically utilize the water tank, in one manner or another, as a functional conduit of sorts to remove air from the toilet bowl and eventually from the room which houses the toilet. The second category requires a special toilet seat or special and often elaborate modifications to the existing toilet seat in one way or another to draw the foul air out of the toilet bowl. These designs are equally applicable to a residential-type water stool -water tank system and the industrial toilets, which do not have a water tank. Neither category of design solution previously disclosed, regardless of the specifics, has seen wide spread use nor significant commercial success, and for good reason; these designs are ineffective, inefficient, unsightly, cumbersome, and costly.
Myriad problems are inevitable when the air exhaust system and water flushing systems share the same apertures, ducts, conduits, and other components, as described in the first category above. Typically, these systems are apt to interfere with the function of the other, thereby rendering each less than fully functional and with inevitable complications. For example, because the flush ring apertures within the toilet bowl, and the ducts/conduits in the toilet stool leading thereto, which disperse the water into the toilet bowl when the water flushing system is in operation, are also the intake apertures for the air exhaust system, the two systems cannot function simultaneously. These systems would require a mechanism to keep the mechanical water flushing system from operating at the same time as the electromechanical air exhaust system. It is preferable to have an air exhaust system which can be fully operational during the water flushing operation, though it is not mandatory; the flushing operation consisting of the flow of the water into, around, and out of the toilet bowl and then through the water trap in the base of the toilet stool and eventually into the sewer/septic system. Even when the systems are not operating concurrently, due to the location and orientations of the flush ring apertures, water and other liquids and potentially solids will invariably get into, and possibly sucked into, the apertures and conduits when the air flow/removal system is operating, thereby interfering with the proper operation of potentially both systems.
In addition to these inherent problems, many retrofitted air exhaust system designs require elaborate mechanical, air flow, and sometimes electrical systems to operate; these systems are bulky, do not blend with the existing toilet system, are often cumbersome, and tend to be expensive. Most of these designs draw the odors through the water tank, which frequently necessitates the elaborate sub systems (mechanical, air flow, and electrical) to reside within the water tank or at least a portion thereof. There is an economy of space within water tanks to begin with; therefore, it would be exceedingly difficult to install the retrofitted air exhaust system, and even more difficult to service either the retrofitted exhaust system or the conventional flush system components within the water tank. These components within the water tank are the only components that typically require servicing or replacement, so easy access thereto is imperative. Another disadvantage to this design is that it will only work with the conventional toilet design, which includes a water tank. An example of this type of design is disclosed in U.S. Pat. No. 5,029,346, which includes, among other modifications to the existing water delivery system, a complicated dual damper system to regulate air flow out of the toilet bowl and through the water tank, which also must be sealed. The system disclosed in U.S. Pat. 5,321,856 is another example of the elaborate, awkward, burdensome, and costly designs which are typical of systems which must be retrofitted to the water tank.
Some of the previous design solutions do not utilize the existing water delivery system in the flush ring to remove air from the toilet bowl but rely on a pipe or manifold or a similar device located within or at the inner periphery of the toilet bowl as the air intake source; U.S. Pat. 4,175,293 is illustrative. While these designs tend not to directly interfere with the water delivery system to the toilet bowl, the waste and water in the toilet bowl can easily interfere with the proper functioning of the air intake source and consequently the entire air exhaust system. Moreover, these devices, such as a pipe or a manifold, are located within the toilet bowl and therefore are prone to getting soiled from common use. These designs will interfere with the clean, clear, contained, and unobstructed discharge into the toilet bowl. The bolder designs that locate the air intake source well within the toilet bowl or are made of malleable materials (to facilitate locating the device within the toilet bowl) could interfere with the swirling action of the flushing/swirling water into and around the toilet bowl, which promotes cleaning and proper drainage/flushing of the water down the trap. Malleable systems also run the risk of being bent or moved into a more obstructing/interfering position. Conventional hand, or similar, cleaning of the toilet bowl would also be obstructed and therefore more difficult, time consuming, and incomplete. These designs fall into the second category of retrofitted systems described above because these systems invariably require changes to be made to the toilet seat design (for either conventional or industrial toilets); locating the intake device within the toilet bowl requires alterations to the existing toilet seat and/or its mounting to the toilet stool or an entirely different, and specially designed and manufactured, toilet seat may be required--different seat designs may also require changes to be made to the toilet stool. Inconvenient and potentially costly retrofitted toilet seats are two more drawbacks of these designs, further flaws to the air exhaust systems which use the seat as an integral component or require seat modifications will be discussed below. As previously noted and discussed, the second category of design solutions to remove foul odors from a toilet bowl utilizes the toilet seat, in one way or another, as the air intake point (source) of the retro-fitted exhaust system. These designs also have drawbacks which render these systems inefficient, ineffectual and/or impractical, as well as cumbersome, unsightly and costly. These retrofitted designs all share one common disadvantage in that there is a plethora of toilet seats and flush ring designs currently on the market with varying shapes, dimensions, colors, materials, and specification. This severely limits the usefulness and marketability of many of these retrofitted seat exhaust systems, regardless of their level of performance. U.S. Pat. Nos. 4,402,091, 4,125,906 and 3,999,225 are examples of seat systems which require careful matching between the existing toilet and the retrofitted parts or entirely new toilet seats.
Many of the seat systems also require the toilet seat, or associated devices to be sealed to the top of the toilet stool and the bottom of the toilet seat--this is but one of many pieces of gadgetry typically required to retrofit existing toilets with an air exhaust system. The need for the seal is an indication of another design flaw common to many of the seat exhaust systems, as well as to design solutions which utilize the water tank but require a seal therewith. Sufficient and effective draw is critical to the proper functioning of these systems but is difficult to achieve with these designs because of the gap between the bottom of the toilet seat and the top of the stool or some other air gap in the water tank, so maintaining tight seals is critical to effective odor removal and minimizing odor drift away from the air intake source.
Many retrofitted designs which utilize the toilet seat, such as the one disclosed in U.S. Pat. No. 5,170,512, have serious design flaws in that the means for drawing air from the toilet bowl is inefficient, ineffective, and interfere with the operation of other toilet devices and systems, and/or is rather complex with elaborate design details and necessary gadgetry. U.S. Pat. 5,170,512 is demonstrative; therein is disclosed a retrofitted toilet seat which draws air from the toilet bowl, however, the distance between the seat apertures and the toilet bowl, in addition to the air gap between the seat and the top of the toilet stool, make this system a particularly inefficient air removal device. Additionally, the system disclosed in the U.S. Pat. No. 5,170,512 relies on the existing ceiling fan, which is often required to reduce the moisture content of the air in the bathroom, to draw the odors out of the toilet bowl via the retrofitted toilet seat. Not only would the odor removal function put an additional "draw load" on the system and thereby interfere with the moisture removal system and make efficient odor removal more difficult, but the extensive distance between the toilet bowl and the fan would also contribute to the inefficacy of the system; unless an extremely large, powerful and probably noisy fan was employed, there would not be enough draw to adequately remove the odors from the toilet bowl. Much of the prior art utilizes existing air ducts to remove the foul air--this is highly inadvisable because the air ducts and conduits may already be at maximum air carrying capacity, so additional flow into that system may cause both systems to back up.
Many of the toilet seat solutions attach the air intake device to the underside of the toilet seat. These designs share the same problem as those described above, including but not limited to: the air gap between the air intake and the toilet stool where the odors are concentrated; the difficulty in cleaning the existing toilet and the retrofitted parts; the structural and aesthetic compatibility problems between the toilet components and the retrofitted parts; and the necessary modifications to the toilet seat. The air gap will be of particular concern because it will contribute to the inefficiency of the system and therefore the effectiveness of the odor removal device. Many systems try to amend this problem with a specially "sealed" toilet seat, which may help, but does not solve the problem of the air intake source being above or outside the toilet bowl and further away from the source of odors than necessary.
Many of the prior art systems which retrofit components of the exhaust system to the seat also retrofit other components to the toilet stool and/or the water tank with the requisite complex integration of the exhaust system components with the toilet stool and/or water tank components. These designs require matching holes, sealing surfaces to moist porcelain, and/or drilling holes into the existing toilet fixtures. Additionally, these designs, as mentioned above, may interfere with and complicate the servicing and cleaning of the toilet stool-water tank system, and/or the bathroom floor plan or design. For the most part, these prior art design solutions are awkward, cumbersome, difficult to clean, and marginally functional.
There are also general design disadvantages common to most of these retrofitted systems which impact the replacement of toilet water flushing system components. Toilet stools and water tanks currently have modular designs to the extent that one is interchangeable with various designs/model/sizes of the other--there only being a flush hole for which the two pieces must be compatible. The flush hole in the toilet stool, typical of the conventional toilet design, transfers the water from the water tank to the toilet stool flush ring. Many of the retrofitted exhaust systems in the prior art require modification to both of these components. Therefore, replacing either the water tank or the toilet stool would require disassembling and reassembling at least a portion of the retrofitted system in order to replace the water tank, water tank components, or the toilet stool. Some of the prior art air exhaust systems locate many of the necessary retrofitted mechanical, air flow, and electrical components exterior to the water tank and toilet stool and do not have this problem. These designs, however, typically do not fit into the design plans for most bathrooms, are awkward and/or unsightly, and make servicing or cleaning the room and toilet water flushing system difficult. Additionally, these components may be awkwardly located and questionably secured to the existing toilet bowl, toilet stool, water tank, wall, or floor and are unwieldy, and typically violate various codes which must be complied with. Water and moisture in the bathroom make retrofitted electrical components within the water tank, on the bathroom floor, or thereby, inherently dangerous.
As just mentioned, another significant problem common to these retrofitted designs is code compliance. These designs may not meet building codes nor be in compliance with the Uniform Plumbing Code because of the location of the additional mechanical as well as electrical components.